Booking 5 tickets on one PNR while waitlisted—what if only some confirm?

Sorry sorry, i know it is a wrong thread, but i thought asking this here will be the best option

I am planning to book a train ticket for 5 members from a single IRCTC account under one transaction (so they share a single PNR). However, the current status is showing a Waiting List.Before I go ahead and book, I want to understand how Indian Railways handles chart preparation for a group booking like this:

1.Can our group get split up? If I book them together, is it possible that 2-3 members get confirmed seats while the other 2-3 stay waitlisted and are completely left behind?

2. What happens in a partial confirmation? If only a few berths clear to Confirmed or RAC status and the rest remain waitlisted, are the waitlisted members still legally allowed to board the train to share the berths, or will their names be dropped from the chart?

3. Automatic Cancellation: If the entire ticket stays fully on the waiting list until chart preparation, will the online system cancel it automatically for all 5 of us?

I want to know if it's safe to book this as a group, or if we risk some members being left on the platform.